Sustainable Air-Conditioning Systems Based on Cold Storage with Comparative Analysis of Efficiency and Costs

The concept behind this undertaking was to create environmentally friendly and sustainable air-conditioning systems supported by energy storage units, as well as to conduct comparative calculations of investment and operational costs to assess their economic viability. In order to meet sustainability requirements, detailed analysis was followed by a decision to utilise cold storage units in which energy is stored through the phase change of water into ice. Aiming to achieve high efficiency, strong reliability and enhanced operational dynamics, a multi-circuit model for coolant flow was developed, incorporating a variable-speed compressor drive. High functionality and performance were attained through the introduction of container vibrations, which resulted in the formation of ice slurry particles in spherical containers placed within an aqueous glycol solution serving as the heat exchange medium. The concept of this technology, along with its accompanying mathematical models, was validated, and the results of this work are presented in the article. To evaluate the competitiveness of air-conditioning systems, the developed solution based on cold storage technology is compared with a lithium-ion battery system and a conventional configuration powered directly by the grid. The results demonstrate that the cold-storage-based air-conditioning system outperforms both reference systems in terms of energy efficiency. An analysis of the full operational cycle indicates that the proposed solution consumes significantly less energy than systems using lithium-ion battery storage. The investment costs are almost twenty percent lower, while service, maintenance and disposal expenses are negligible. These attributes make it a competitive solution that is both economically and environmentally sustainable. In summary, the proposed technology fully satisfies the key principles of sustainability. It does not deplete natural resources, minimises the environmental impact, offers long-term reliability and contributes to lower energy bills and more responsible resource use.